David Young
Technical Subject Areas
1. Subject – Navigation.
2. Introduction – Most pilots enjoy taking cross-country flights. It can be quite a thrill to
successfully get yourself from one point to another without the help of others. However,
before you can do this, you must learn the fine art of navigation. There are many ways to
navigate safely, and a combination of those different ways will assure the safest flight
possible.
3. Outline –
a. Discuss the variety of terms used in navigation.
b. Discuss aeronautical publications.
i. Discuss sectional charts.
ii. Discuss the airport facility directory.
c. Explain how to plot a course.
d. Discuss how to select a safe altitude.
e. Discuss dead reckoning.
f. Discuss pilotage.
g. Discuss radio navigation.
h. Discus diversion procedures.
4. Contents –
a. The standard temperature at sea level is 15º C, and the standard pressure is 29.92
inches of mercury (Hg).
b. There are several different types of airspeeds: indicated, calibrated, equivalent,
and true (ICE T acronym).
i. Indicated (KIAS) – the airspeed read right off of the airspeed indicator.
1. This speed is measured by the difference between ram air, or the
air entering the pitot tube, and static air, or air that is not moving.
ii. Calibrated (KCAS) – the indicated airspeed corrected for position error
and installation error.
1. Position error is simply an error that may result from the
misreading of the static air.
a. This usually occurs at high angles of attack.
2. Installation error is a known error that is calculated during the
installation of the air-sampling devices.
iii. Equivalent (KEAS) – the calibrated airspeed corrected for compressibility
error.
1. Compressibility error comes from the rapid compression of air into
the pitot tube at higher airspeeds.
2. This is generally not much of a concern for trainer GA aircraft, but
it does become one as you begin flying faster than about 200 kts.
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iv. True (KTAS) – the equivalent airspeed corrected for altitude and
nonstandard temperature.
1. This is useful for flight planning purposes.
c. Groundspeed (GS) is a measurement of how fast the aircraft moves across the
ground.
i. It may be difficult to understand how an aircraft can move through the air
at a different rate than over the ground, so here is an example:
1. Pretend we are flying along at 500 kts when we suddenly
encounter a 100 kt tailwind.
a. Our airspeed indicator will still indicate 500 kts, but our
groundspeed will jump to 600 kts because the tailwind is
pushing us faster across the ground (refer to Figure A).
2. Pretend we are flying along at 500 kts when we suddenly
encounter a 100 kt headwind.
a. Our airspeed indicator will still indicate 500 kts, but our
ground speed will decrease to 400 kts because the
headwind is reducing the rate at which we cover ground
(refer to Figure B).
3. In both these cases, we fly through the air at 500 kts, but unlike the
ground, the air can move.
a. If the air moves with us, and we still travel through the air
at the same airspeed, and the tailwind adds to our
groundspeed. If the air moves against us, we still travel
through that air at the same speed, but our groundspeed is
reduced.
d. There are several different types of altitudes: indicated, absolute, true, pressure,
and density.
i. Indicated – the altitude read right off the altimeter when it is set to the
local altimeter setting.
1. It is measured by an aneroid barometer inside the altimeter. As the
aircraft ascends, the pressure on the barometer decreases, and the
altimeter indicates an increase in altitude.
2. As the aircraft descends, the pressure on the barometer increases,
and the altimeter indicates a decrease in altitude.
ii. Absolute (AGL) – the vertical distance, in feet, above the ground level.
iii. True (MSL) – the vertical distance, in feet, above mean sea level.
1. Airports, terrain, and obstacles are all reported in MSL, although
an AGL reading may be given in addition to the MSL altitude.
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iv. Pressure – the altitude indicated on the altimeter when the altimeter
setting window is set to 29.92” Hg (the standard pressure setting at mean
sea level).
1. This is the altitude above the standard datum plane, which is a
theoretical plane where air pressure (corrected to 15º C) equals
29.92 “ Hg.
2. Pressure altitude is used to calculate density altitude, true altitude,
true airspeed, and other performance data.
v. Density – the pressure altitude corrected for nonstandard temperature.
1. This is the altitude the aircraft “feels” like it’s at.
2. For example, if it is really hot out, the aircraft will “feel” like it is
at a higher altitude because of the decrease in performance. The
opposite is true for really cold days.
3. This altitude is often used for performance calculations because it
directly relates to the aircraft’s performance at altitude.
e. To help you remember if your altimeter will indicate a higher or lower altitude
than what you are really at because of non-standard temperature or pressure, use
the aid “Hot to cold or high to low, look out below!” (refer to Figure C)
i. Basically, if you are flying from an area of warm air to an area of cold air,
the cold air has less outward pressure on the air around it. Therefore, the
altimeter will sense that you are higher than you really are, which means
that you might run into traffic below your indicated altitude.
ii. The same principle holds true for flying from high pressure to low
pressure.
f. When referring to the direction an aircraft is going, it is extremely important to
note the difference between heading and course (refer to Figure D).
i. Heading – the direction the aircraft’s nose is pointed (in reference to
north).
ii. Course – the direction the aircraft is travelling.
1. If any crosswind exists, the heading will not be the same as the
course.
iii. To go from course to heading, you must factor in a wind correction angle
(WCA), or the angle formed between the desired course and the heading
needed to maintain that course.
g. There are several different types of headings/courses: true, magnetic, and
compass.
i. Most people think of the North Pole as the very northern top of the world.
1. This is what we call the true North Pole.
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ii. However, there exists a magnetic field in the earth (refer to Figure E).
The magnetic North Pole rests on the top of the magnetic field, and it
continually changes its location as the earth’s magnetic field changes.
1. The magnetic North Pole is important to us because our compasses
point to magnetic north instead of true north.
2. Usually, the magnetic North Pole is somewhat near the true North
Pole. The distance measured between them is the magnetic
variation (refer to Figure F).
a. Lines that connect areas of equal magnetic variations are
called isogonic lines.
b. The line connecting the areas where the magnetic variations
equal zero is called the agonic line.
iii. True – the heading/course of the aircraft with respect to true north.
iv. Magnetic – the heading/course of the aircraft with respect to magnetic
north.
1. This is obtained by adding magnetic variation, or the number of
degrees the magnetic North Pole is from the true North Pole.
a. This is different for every part of the world, and it is shown
on the maps as on Figure G.
v. Compass – the heading/course of the aircraft corrected for magnetic
deviation.
1. Metal and electrical parts in the aircraft change the magnetic field
felt by the magnetic compass. Therefore, the deviation, or the
compass error from the magnetic field disturbance, is calculated to
help you know by how much your magnetic compass is off for
given headings.
a. Usually, the deviation is published for 45º increments in
headings i.e. it will give you the deviation for 360º, 45º,
90º, 135º, etc...
vi. To help you remember all this, use the pneumonic “TV Makes Dumb
Children. In other words, to go from True to Magnetic, add Variation. To
go from Magnetic to Compass, add Deviation.
vii. To go from a course to a heading, add your WCA.
h. Before you go on to planning your flight, it is important to have some sort of
navigation log that can be used to record all of the numbers you will need to know
for your flight.
i. If you do not have access you a navigation log, then you may use one from
the internet, or make one yourself with the same columns and rows you
see here: http://www.flightplan.za.net/navLog.pdf
i. To actually begin navigating, you must have some sort of map to use.
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i. The government release sectional charts that are good for 56 days.
ii. These charts provide visual information on airports, controlled airspaces,
obstructions, cities, radio aids, natural terrain (i.e. rivers and mountains),
along with much more (refer to Figure H).
iii. Refer to an Airport Facility Directory (AFD) to give you a TON of
information about every airport that is in the region that AFD covers
(multiple AFDs are used to cover the entire United States).
1. These also expire every 56 days.
2. This can also help you plan on where you should go.
a. If you want to go to the Chicago area, but you need a
certain type of fuel, that information will be listed in the
AFD, and you can decide where you should go to get the
service you need.
j. The first step in navigation is drawing a straight line (with a ruler or plotter)
between your departure airport and your destination airport.
i. Let it be known that you can break the course up into many segmented
circles, but it is easiest for a beginner to only have one course line.
ii. Once you have the line drawn, you need to measure the distance between
your departure airport and your destination airport.
1. To do this, make sure that your ruler on your plotter is the
“Sectional” side and NOT the “WAC” side.
2. Put the zero mark on your departure airport, and line the ruler up
with your course line.
3. Mark off where the destination airport is on you plotter, and that
will be the distance from your departure airport.
iii. Once you have the distance measured, you need to determine exactly what
course (in degrees) will get you there.
1. For example, if the destination airport is due east of the departure
airport, then the course is 90º.
2. If your course is oriented more east-west, then try to find a place
on your course near the middle of your line that intersects a
meridian, or line of longitude.
a. Place the plotter’s hole over that intersection and line the
plotter up with your course line.
b. Read the course off of the outer scale.
3. If your course does not pass over any meridians, then repeat the
same process as above, but this time place the hole over a line of
latitude.
a. Use the inner scale to determine your course.
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k.
l.
m.
n.
iv. Once you have the distance and course measured, record them in your
navigation log.
Now, you must begin selecting checkpoints that you can use along your route of
flight to help keep you on course.
i. The best checkpoints are towns, airports, and distinguishable terrain
characteristics (i.e. rivers and lakes), followed by roads and unique
features (power plants), followed railroads and large power lines..
1. Basically, you want the landmark to be large and identifiable from
a high altitude, but you do not want it so large that it is hard to tell
if you are over the right part of it (i.e. don’t choose all of Chicago
as a checkpoint).
2. If the point is too small, then it will be difficult to see from the air,
so it is equally useless to us.
ii. After completing your performance charts (which is discussed in another
technical subject area), choose your first waypoint to be the distance it will
take you to reach your cruise altitude from your departure airport.
1. For example, if it will take you 9 miles to get to cruising altitude,
your first checkpoint should be 9 miles away.
iii. Choose another checkpoint about 10 miles from your first checkpoint.
iv. Choose another checkpoint about 20 miles from the second checkpoint.
v. Keep choosing checkpoints 20 miles from the previous checkpoint until
you begin getting close to your destination airport.
vi. You should try and find a waypoint that is the same distance away from
the destination airport as it will take you to get from cruise down to traffic
pattern altitude.
1. For example, if you will descend from cruise in 8 miles, have your
“descent checkpoint” be approximately 8 miles from your
destination.
vii. Finally, mark the destination airport as your last checkpoint.
Now that you have all of your checkpoints chosen, you must measure the distance
between each checkpoint and the point before it and record those values in the
“Distance” column in the corresponding rows.
You must also fill out the magnetic variation near each checkpoint.
i. Use a ruler if you need to determine which isogonic line is closer to your
checkpoint if two are close.
ii. If the magnetic variation is to the west, then add that value to your true
course to get magnetic course.
iii. If the magnetic variation is to the east, then subtract that value to your true
course to get magnetic course.
Next, you must determine what altitude you are going to cruise at.
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i. First and foremost, you must choose an altitude that will permit a safe
flight i.e. clearance from obstacles.
ii. If you are flying above 3,000 ft AGL, you are to fly on certain altitudes
going in a easterly heading and other altitudes on a westerly heading.
1. If your magnetic course is between 360º and 179º, then you must
fly at an odd altitude plus 500 feet i.e. 5,500 ft.
2. If your magnetic course is between 180º and 359º, then you must
fly at an even altitude plus 500 feet i.e. 4,500 ft.
3. This ensures that traffic going in opposite directions will most
likely not be running into one another as they are flying towards
each other.
o. Now that you know your altitude, you may check the winds aloft along your route
to determine what the winds will be at altitude.
i. To access this information, you may check on the internet at DUAT.com
or through 1-800-wx-brief.
ii. These are usually reported at 3,000 ft intervals.
iii. If your altitude is not within 1,000 ft of any of the given winds aloft
values, then you may interpolate between the value for the altitude above
you and the value for the altitude below you.
iv. It may be necessary to record the winds aloft for multiple stations along
your route if your trip is long enough.
p. Once you know your winds aloft, it is time to calculate your WCA, magnetic
heading, and compass heading.
i. Use the instructions on your E6B, and use the true airspeed you calculated
from your performance charts when you are prompted to input the true
airspeed.
1. The basic steps are as follows:
a. Put the grommet over a datum value (use 100 as it is the
easiest to measure from), put the winds aloft value under
the True Index.
b. Using a pencil, mark the wind velocity up from the
grommet by taking the wind velocity, adding it to 100, and
marking that value along the vertical axis.
i. For example, if the wind speed is 24 kts, mark 124
kts along the vertical axis.
c. Set your true course under the True Index and slide the
pencil marking up to the arched line that corresponds to
your true airspeed.
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d. Read the WCA as the angle between your pencil mark and
the vertical axis (WCA is negative if the pencil mark is on
the left, otherwise its positive if on the right).
e. Your groundspeed will read under your grommet.
ii. Fill in the GS and the WCA on your navigation log.
iii. Add or subtract your WCA to your magnetic course to get magnetic
heading.
iv. Finally, add or subtract your compass deviation (usually written under the
magnetic compass in the aircraft for certain headings) to your magnetic
heading to get compass heading.
q. Since we now know what our GS will be and what the distances are between our
checkpoints, we can calculate our estimated time enroute (ETE) from checkpoint
to checkpoint.
i. Using the E6B once again (this time on the other side), line up your Rate
Arrow with your calculated GS on the outside ring.
ii. To figure out your ETE from point to point, keep the Rate Arrow where it
is and find the distance written from a checkpoint to another.
1. Find the distance along the outer ring (divide by 10 if you have to,
but then remember to divide the time by 10 as well), go straight
down from that point to the inner ring, and that value is your ETE
in minutes.
iii. Continue this for all your checkpoints.
iv. Then, add up all your ETEs to get your estimated total time enroute.
v. According to FAR 91.151, you must have enough fuel to get from your
departure airport to your destination airport, then be able to fly for:
1. 30 minutes during the day; or
2. 45 minutes at night.
r. Before we begin our trip, we must fill out and file a flight plan.
i. If you do not have a flight planning form, you may make one yourself
based on the example available in AIM 5-1-4.
1. Select VFR for TYPE.
2. Write the tail number in A/C IDENTIFICATION.
3. Consult your POH to check and see what equipment you have
from AIM 5-1-8 (called an equipment suffix).
4. For an Archer write PA-28/[equipment suffix], or for an Arrow write
PA-28R/[equipment suffix] in the A/C TYPE/SPECIAL EQUIPMENT.
5. Write down your TAS in the TRUE AIRSPEED box.
6. Write down the ICAO identifier of your departure airport in
DEPARTURE POINT.
7. Write down your proposed departure time in Zulu in PROPOSED
DEPARTURE TIME.
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8. Write down your cruising altitude in CRUISING ALTITUDE.
9. Write “Direct” in your ROUTE OF FLIGHT.
10. Write down the ICAO identifier of your destination airport in the
DESTINATION.
11. Add 10 minutes to your total ETE and put that in your ESTIMATED
TIME ENROUTE.
a. The extra time is added to account for being vectored around by
air traffic control or any unseen problems throughout the flight
that may cause the flight to be longer.
12. Write any pertinent remarks in the REMARKS section i.e. “Student
training.”
13. Write down your calculated fuel on board in FUEL ON BOARD.
14. Skip the alternate Airport box.
15. Write down your name, address, telephone number, and A/C home base
(i.e. CMI) in the PILOT’S NAME box.
16. Write down the number aboard the aircraft in NUMBER ABOARD.
17. Write down the color of your aircraft in COLOR OF AIRCRAFT i.e.
“White with orange.”
ii. Next, file the flight plan with a briefer on 1-800-wx-brief.
1. Tell them you would like to file a VFR flight plan, and just slowly read
off the information in the order listed above.
2. Be sure to get a weather report from the briefer as well.
s. You are now ready to go fly.
t. After preflighting the aircraft and taxiing to the runway, set some sort of timer as
you taxi on to the runway for takeoff. Also, note the time off on your flight
planning sheet.
u. As soon as it is safe to be doing so, begin calculating your ETA for each
checkpoint by adding the ETE to the previous ETA.
i. For the first checkpoint, add the ETE to the takeoff time, and record that
as your ETA.
ii. For all subsequent checkpoints, add the ETE to the previous entry’s ETA.
v. After taking off, try to get on course as quickly as possible.
i. To do this, it may be necessary to fly a heading that will intercept your
course.
1. For example, if you took off from runway 22 and your on-course
heading is 360º, you may need to turn to about 40º to intercept
your course.
2. Once on course, turn back to a heading of 360º.
ii. To know when you are on course, use ground reference points that lay on
the very beginning of your course.
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iii. Once you have overflown those reference points, turn to an on-course
heading.
iv. If you have a VOR on field, the easiest way to get on course is to dial in
your course on the OBS, and fly an intercept heading until the OBS
centers up. Then turn on-course.
w. As soon as you are out of your departure airport’s airspace, call up the nearest
Flight Service Station (FSS) to open your flight plan.
i. Look for VORs with brackets containing a geographic name under the
VORs information box.
ii. If it contains a name, then you may call them up on the frequency listed
above.
1. Note that if the frequency is NOT listed with an ‘R’ after it, then
you may proceed as normal.
2. If that frequency DOES have an ‘R’ after it, then you must
transmit over that frequency and listen to the response from FSS
on the VOR frequency.
3. This means you must turn that NAV radio’s ID and volume up, as
well as turning on its speaker.
iii. The conversation should go as follows:
You: “[geographic name listed] Flight Service, Archer [tail
number] is with you transmitting on [transmission frequency] and
receiving on [receiving frequency].”
FSS: “Archer [tail number], go ahead.”
You: “[geographic name listed] Flight Service, Archer [tail
number] would like to open up my VFR flight plan to [ICAO
identifier of destination]. Time off was [takeoff time].”
FSS: “Archer [tail number], your VFR flight plan has been
opened. Good day.”
x. One type of navigation is called dead reckoning.
i. This type of navigation involves simply flying a heading, which is
corrected for wind, in order to fly from one point to another.
ii. To use it, you must continually update your groundspeed, ETA, and WCA
at every checkpoint.
1. By correcting these, you will stay on the course drawn from your
departure airport to your destination airport.
2. To recalculate your WCA, simply determine what heading is
keeping you on course, and subtract that magnetic heading from
your magnetic course.
a. You should hold that amount of wind correction in your
heading to maintain course.
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y. Another type of navigation is called pilotage.
i. As you fly along, you should be looking for your checkpoints along with
any other distinguishable landmarks to help you maintain your course.
1. This is why we picked the checkpoints along our course.
ii. Be sure that you carefully look at the landmarks around you as one
landmark may look like another at first glance.
1. Always look for the big picture
2. Look at the general shape of the landmark, anything
distinguishable around it i.e. roads, rivers, railroads, etc…
z. The last type of navigation involves the use of radio aids.
i. One type of radio aid is the VOR, or Very High Frequency Omnidirectional Radio Range.
1. Think of it as a radio station that shoots out 360º lines (one for
every degree of heading).
a. These lines are called radials, and each radial is called by
its three-digit representation of the heading the radial is in.
i. For example, the radial that shoots out directly east
of the VOR is the 090 radial because it shoots out
90º from the VOR.
b. By knowing which radial we are on, we can know our
position in relation to a VOR.
i. We use an instrument called an Omni-bearing
Selector (OBS) to help us figure out where we are
in relation to the VOR (refer to Figure I).
ii. It should be noted that heading has NOTHING to
do with our indication on the OBS. Rather, our
LOCATION in reference to the VOR is important.
2. To dial in a certain radial, we rotate the card on the OBS around
until that radial’s number is centered at the top.
3. The course deviation indicator (CDI) is the needle we see on the
OBS. You can think of this as the radial itself.
4. There is also a TO/FROM flag.
a. If you center up the CDI with a TO indication, the course
that centers up the CDI is the course you must fly to get TO
the VOR.
b. If you center up the CDI with a FROM indication, the
course that centers up the CDI is the course you must fly to
go AWAY from the VOR.
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5.
6.
7.
8.
c. Note that as if you have the CDI centered with a TO
indication and you fly directly over the top of the VOR, the
flag will switch to a FROM indication.
Once you have a course centered up, fly a heading that will keep
you on that course and the CDI centered.
a. If you are flying to the station and you have a TO
indication, then always fly TOWARDS the needle.
i. The same applies if you are flying from the station
with a FROM indication.
b. It is possible to fly towards the station and get a FROM
indication, and this happens when you put the course that is
reciprocal to the course needed to get to the station.
i. This will create reversed sensing, which means that
you now must fly away from the needle.
c. IMPORTANT: it is good practice to avoid reverse sensing.
So, if you need to fly to the VOR, center up a course that
will get you to the VOR. If you need to fly away from the
VOR, center up a course that will get you away from the
VOR.
Refer to Figure J for an example of what you must do to track a
radial in a crosswind.
So to actually navigate with VORs, center up the CDI with a
course that will get you to the station with a TO flag.
a. This will require you to know relatively where you are in
relation to the VOR i.e. am I north, east, south, or west of
the VOR?
b. This will get you going directly to the VOR.
c. From there, select another VOR along your route and
repeat this procedure.
d. Keep in mind that, for flight planning purposes, you should
not plan to use a VOR from further that 40 NM away from
it.
i. You might be able to pick up a signal from that far
out, but it isn’t guaranteed, so you should not rely
on getting signal any further out that 40 NM.
Something called distance measuring equipment (DME) may help
you in determining your distance from a VOR.
a. DME measures the amount of time that it takes for radio
waves to be sent from the aircraft to a DME station (many
times coupled with a VOR). This time is then converted
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into distance, which can even be converted into
groundspeed.
b. Note that the distance given is NOT the distance across the
ground, but rather the distance from you up in the air, to the
DME station on the ground, otherwise known as slant
range.
c. For example, if you were 5,280 ft directly above a DME
station, the DME would read 1 mi even though you are
directly overhead the station.
ii. Another type of radio aid is the non-directional beacon (NDB).
1. Think of this as a stupid VOR.
2. In this case, there are no radials that shoot out of the NDB.
Instead, you have an instrument called the automatic direction
finder (ADF), which always points towards the station, no matter
what.
3. Unlike a VOR, this time, your heading does matter.
a. For example, if your nose is headed straight towards the
station, the needle would point to the very top of the
instrument.
b. However, if you turned to the right by 20º, that needle
would swing 20º to your left because you must fly 20º to
the left to get the needle back off your nose.
4. Two important NDB terms are relative bearing and magnetic
bearing.
a. Relative Bearing (RB) – the value to which the needle
points on the azimuth dial (the compass rose around the
instrument).
i. For example, if the NDB is 40º to your right, your
relative bearing to the station is 40º.
ii. For example, if the NDB is 40º to your left, your
relative bearing would be 360º - 40º = 320º.
b. Magnetic Bearing (MG) – “to” the station is the angle
formed by a line drawn from the airplane to the station and
a line drawn from the airplane to magnetic north.
i. MB is different than relative bearing because
relative bearing is only the number of degrees you
must turn right to head straight for the NDB.
ii. Magnetic bearing is the actual course you must
track to get to the NDB.
c. Remember that RB + MH = MB.
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i. It may be necessary to subtract 360º from this
equation if the MB is above 360º.
d. To get the MB FROM the station, add 180º to the MB TO
the station.
e. Refer to Figure K for a visual of RB and MB.
i. In this case, our relative bearing would be what the
needle points to, or about 225º.
ii. The magnetic heading is 030º.
iii. So to get to the station, we must track a course of
255º from our present location.
f. While flying, we will almost always have some sort of
crosswind.
i. As we correct for the crosswind by crabbing, our
ADF indication will change because we have
moved our nose with relation to the station.
ii. If our WCA is 10º to the right of course, then our
ADF should point to 10º left (or a RB of 350º).
iii. For example, if our MB to the station is 340º and
we must hold a heading of 330º to correct for the
wind, our ADF would indicate a RB of 10º.
iv. If you are holding a WCA in, but the ADF begins to
move further and further from the top of the
instrument, then our crab angle is too much, and we
should reduce it to stay on course.
g. When flying outbound on an NDB, the needle on the ADF
will point towards the bottom of the instrument.
i. The fundamentals of flying away from an NDB are
the same as flying towards it, but this time the wind
correction procedure is different.
1. Wind correction should be made in the
direction opposite of that in which the
needle is pointing.
5. The last radio aid is the global position system (GPS).
a. This system uses satellites orbiting the earth to pinpoint the
exact location of the aircraft.
b. To do this, an aircraft needs at least four satellites.
i. The satellites send out ultra-high frequency radio
waves that are received by both GPS antennae and
control segments.
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1. GPS antennae are those found on aircraft
and cars.
2. The control segment consists of control
stations across the globe that update each
satellites EXTREMELY accurate atomic
clocks.
ii. The satellites continually send out radio waves that
contain the exact time of emission from the satellite.
iii. When the GPS antennae receive the radio wave,
they measure the difference between the current
time and the time the satellite’s radio wave was
sent, and compute the distance.
c. Each of the four satellites the GPS antenna is using gives
the user a better and better idea of exactly where they are
laterally, longitudinally, and vertically in relation to the
earth.
d. This information is then usually displayed visually on a
map.
i. This map can make the process of finding out
exactly where you are in relation to towns, airports,
and other radio aids a cinch.
e. A useful function that you can use for GPS navigation is
the “Direct to” function.
i. Basically, you can input any airport or navigational
aid (such as a VOR or NDB) and have the map
draw out a course for you to fly to get from where
you are to that point.
ii. This is obviously useful in navigation because you
can see on a map how to get back on course
without having to do a lot of math and drawing
yourself.
aa. Ideally, a combination of all these radio aids should be used to help you maintain
the best situational awareness possible when navigating.
i. Using dead reckoning to get from point A to point B while reaffirming
your location with pilotage, VORs, and GPS is the best way to make sure
that you get from point A to point B safely.
bb. If at any time you feel you must divert to a new airport because of bad weather,
sick passenger, equipment malfunction, or lack of fuel (to name a few), there is a
list of steps you should follow.
Young 16, II-F
i. First, start a timer (this will be helpful in calculating your groundspeed
later).
ii. Then, find where you are on the map and mark it.
iii. Choose an appropriate alternate airport (one which will have the services
you need or the one that is closest, depending on the nature of your
diversion).
iv. Turn to a heading that will roughly get you flying in the direction of that
airport.
v. Draw a straight line from the point you marked on the map to your new
destination and measure the distance.
vi. To find out the new course, you can slide your plotter to a VOR compass
rose while keeping the plotter parallel to your course line.
vii. Read the course off the compass rose.
viii. Next, figure out the WCA with the winds aloft.
ix. Using magnetic variation and deviation, calculate your new magnetic
heading.
x. Also, calculate your groundspeed in the same way you did during your
flight planning.
xi. With the groundspeed and distance information, calculate your ETA to the
new destination.
xii. Choose checkpoints along your route of flight and calculate the distance
and ETA to those points.
xiii. Calculate your fuel burn by multiplying your gallons/hour by the number
of hours it will take you to get to the destination (be sure to convert your
ETA to hours).
5. Evaluation –
a. The student can successfully explain the defined terms.
b. The student can briefly explain the aeronautical publications listed above.
c. The student can run through the steps of flight planning (have him/her practice
this with your supervision).
d. The student can adequately define and explain dead reckoning, pilotage, VORs,
NDBs, and GPS.
e. The student can run through the steps of diverting the aircraft.
6. References –
a. PHAK, Ch. 14
b. Gleim’s Flight Instructor Flight Maneuvers, Part II, Unit II
Young 17, II-F
Figure A
Figure B
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Figure C
Figure D
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Figure E
Figure F
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Figure G
Figure H
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Figure I
Young 22, II-F
Figure J
Young 23, II-F
Figure K